【LeetCode】15. 三数之和

class Solution {
public:
    vector<vector<int>> threeSum(vector<int>& nums) {
        vector<vector<int>> result;
        sort(nums.begin(), nums.end());
        for(int i = 0; i < nums.size();i++)
        {
            if(nums[i] > 0) return result;
            if(i > 0 && nums[i] == nums[i-1]) continue;  
            int left = i + 1; 
            int right = nums.size()-1;
            while(left < right)
            {
                if((nums[i] + nums[left] + nums[right]) < 0) left++;
                else if((nums[i] + nums[left] + nums[right]) > 0) right--;
                else{
                    result.push_back(vector<int>{nums[i], nums[left], nums[right]});
                    while(left < right && nums[left] == nums[left+1]) left++;
                    while(left < right && nums[right] == nums[right-1]) right--;
                    right--;
                    left++;
                }
            }
        }
        return result;
    }
};